Hello,
Does anyone know of a supplier who makes a replacement bottom tank for the 2416 radiator?Mine has rotted out badly.
It is made of cast iron and has the 6 mounting lugs on the edges and the 2 large water inlets which are sealed to the cylinder housing by 2 orings

This seams to be a general problem on the later Bulldogs. My radiator must
have been leaking, as somebody fixed it with a brass plate and liquid metal.
If the egdes, guiding the o-ring gaskets, are not yet complete gone, you could
try to use some liquid seal, additionally.
If you like, I could paste some pics of mine, showing the repair.

I am going to take the radiator to a repair shop to see if the bottom tank can be removed.If he can remove it,I will sandblast it to clean up the metal and to check on how much rot there is.Hopefully then cut out the rot sections and braze some metal sections in place .

If the bottom tank can not be easily removed I am very interested in suggestions,such as liquid metal and repair plates,fibreglass etc.

The radiator repair shop did not want to remove the bottom tank because the heat required on the cast iron base would create more leaks and problems in the radiator construction.

I will be trying the repair you have done using brass sheet and some metal cement such as devcron or jb weld.I have sandblasted the base and will sandblast the brass sheet to try and get the metal cement to adhere properly.

I have an Allgaier A12 with a frost cracked cylinder housing about 8cm long.I ground the crack into a v and used the devcron in the crack and it has worked well so far.There is no indication of a leak and you can not see the repair so the devcron must be good stuff.

As I wrote before, this repair was not my job. This must have been
done centuries ago, but I did not recognize any leak, so it works fine.

I googled the devcon material, you want to use, looks not bad to me.
Quite expensive, but if it works, the price is the minor issue.
They supply a lot of different types, which one did you use for the cylinder
housing?